The present invention relates to an improved cup and lid design for insuring that users do not inadvertently remove the lid from the cup and for allowing cups to be stacked.
Insulated drinking cups for holding hot liquids and cold liquids are well known in the prior art. U.S. Design Pat. No. 314,309 to Thorp illustrates one such drinking cup. As can be seen from this patent, the handle used with this drinking cup is designed to have an upper portion on which a user can rest his/her thumb as the liquid within the cup is being consumed. Unfortunately, the design of this handle allows the end of the user's thumb to contact the cup sidewall in an area adjacent the rim. As a result, it is possible for a user, resting his/her thumb on the handle, to inadvertently catch a lid covering the cup and dislodge it from the cup. This can be a particularly dangerous problem if the liquid in the cup is extremely hot. This problem becomes even more serious in certain institutional settings wherein the users are elderly or infirm people.
Institutional use of drinking cups of the type shown in the aforesaid patent often requires filled drinking cups to be stacked for distribution purposes. Thus, there is a need for cup lids which are positively sealed to the cup and which enable sealed cups to be stacked in a secure manner.